diff --git a/tests/states_group.py b/tests/states_group.py
new file mode 100644
index 00000000..8593cea3
--- /dev/null
+++ b/tests/states_group.py
@@ -0,0 +1,102 @@
+import pytest
+
+from aiogram.dispatcher.filters.state import State, StatesGroup, any_state, default_state
+
+
+class MyGroup(StatesGroup):
+    state = State()
+    state_1 = State()
+    state_2 = State()
+
+    class MySubGroup(StatesGroup):
+        sub_state = State()
+        sub_state_1 = State()
+        sub_state_2 = State()
+
+        in_custom_group = State(group_name='custom_group')
+
+        class NewGroup(StatesGroup):
+            spam = State()
+            renamed_state = State(state='spam_state')
+
+
+alone_state = State('alone')
+alone_in_group = State('alone', group_name='home')
+
+
+def test_default_state():
+    assert default_state.state is None
+
+
+def test_any_state():
+    assert any_state.state == '*'
+
+
+def test_alone_state():
+    assert alone_state.state == '@:alone'
+    assert alone_in_group.state == 'home:alone'
+
+
+def test_group_names():
+    assert MyGroup.__group_name__ == 'MyGroup'
+    assert MyGroup.__full_group_name__ == 'MyGroup'
+
+    assert MyGroup.MySubGroup.__group_name__ == 'MySubGroup'
+    assert MyGroup.MySubGroup.__full_group_name__ == 'MyGroup.MySubGroup'
+
+    assert MyGroup.MySubGroup.NewGroup.__group_name__ == 'NewGroup'
+    assert MyGroup.MySubGroup.NewGroup.__full_group_name__ == 'MyGroup.MySubGroup.NewGroup'
+
+
+def test_custom_group_in_group():
+    assert MyGroup.MySubGroup.in_custom_group.state == 'custom_group:in_custom_group'
+
+
+def test_custom_state_name_in_group():
+    assert MyGroup.MySubGroup.NewGroup.renamed_state.state == 'MyGroup.MySubGroup.NewGroup:spam_state'
+
+
+def test_group_states_names():
+    assert len(MyGroup.states) == 3
+    assert len(MyGroup.all_states) == 9
+
+    assert MyGroup.states_names == ('MyGroup:state', 'MyGroup:state_1', 'MyGroup:state_2')
+    assert MyGroup.MySubGroup.states_names == (
+        'MyGroup.MySubGroup:sub_state', 'MyGroup.MySubGroup:sub_state_1', 'MyGroup.MySubGroup:sub_state_2',
+        'custom_group:in_custom_group')
+    assert MyGroup.MySubGroup.NewGroup.states_names == (
+        'MyGroup.MySubGroup.NewGroup:spam', 'MyGroup.MySubGroup.NewGroup:spam_state')
+
+    assert MyGroup.all_states_names == (
+        'MyGroup:state', 'MyGroup:state_1', 'MyGroup:state_2',
+        'MyGroup.MySubGroup:sub_state',
+        'MyGroup.MySubGroup:sub_state_1',
+        'MyGroup.MySubGroup:sub_state_2',
+        'custom_group:in_custom_group',
+        'MyGroup.MySubGroup.NewGroup:spam',
+        'MyGroup.MySubGroup.NewGroup:spam_state')
+
+    assert MyGroup.MySubGroup.all_states_names == (
+        'MyGroup.MySubGroup:sub_state',
+        'MyGroup.MySubGroup:sub_state_1',
+        'MyGroup.MySubGroup:sub_state_2',
+        'custom_group:in_custom_group',
+        'MyGroup.MySubGroup.NewGroup:spam',
+        'MyGroup.MySubGroup.NewGroup:spam_state')
+
+    assert MyGroup.MySubGroup.NewGroup.all_states_names == (
+        'MyGroup.MySubGroup.NewGroup:spam',
+        'MyGroup.MySubGroup.NewGroup:spam_state')
+
+
+def test_root_element():
+    root = MyGroup.MySubGroup.NewGroup.spam.get_root()
+
+    assert issubclass(root, StatesGroup)
+    assert root == MyGroup
+
+    assert root == MyGroup.state.get_root()
+    assert root == MyGroup.MySubGroup.get_root()
+
+    with pytest.raises(RuntimeError):
+        any_state.get_root()